nagashTue, Dec 8, 2009 Marius, I saw this kind of question everywhere the day I was reading on this subject... people are always puzzled with the origin of the extra mass, but it's a misconception. the answer here is density, not mass. planets seems to evolve from dense and heavy rocks, get slowly wet and bigger until they turn into cold gas giants... it's odd to think about planets like some kind of bubbles, because the time it takes for these changes to take place are beyond our imagination. but, hey, science already study the evolution cycles of stars... why should planets be static? I find it amazing to imagine that Jupiter was once an Earth-like planet, and slowly evaporated until it got 1000 times bigger : )
another mind-bending aspect of this theory is the idea that gravity increase while Earth expands. it not only makes sense, but also explain the giant size of the fossils we find - archeologists still wonder how some dinosaur species could move such big heads without breaking their necks, and in fact, it could be impossible with current gravity. that's why we don't have giant lyzards anymore. same thing with insects, they just can't possibly be bigger or their exoskeleton would collapse. still, once upon a time, giant dragonflies roamed the earth...
Marius, I saw this kind of question everywhere the day I was reading on this subject... people are always puzzled with the origin of the extra mass, but it's a misconception. the answer here is density, not mass. planets seems to evolve from dense and heavy rocks, get slowly wet and bigger until they turn into cold gas giants... it's odd to think about planets like some kind of bubbles, because the time it takes for these changes to take place are beyond our imagination. but, hey, science already study the evolution cycles of stars... why should planets be static? I find it amazing to imagine that Jupiter was once an Earth-like planet, and slowly evaporated until it got 1000 times bigger : )
another mind-bending aspect of this theory is the idea that gravity increase while Earth expands. it not only makes sense, but also explain the giant size of the fossils we find - archeologists still wonder how some dinosaur species could move such big heads without breaking their necks, and in fact, it could be impossible with current gravity. that's why we don't have giant lyzards anymore. same thing with insects, they just can't possibly be bigger or their exoskeleton would collapse. still, once upon a time, giant dragonflies roamed the earth...